This invention relates to a linear motor powered remotely controlled shunt trip operator for a bolted pressure contact swatch that utilizes the positive linear displacement of a rod of a linear motor to rotate the operating shaft of the shunt trip operator in its closing direction.
A shunt trip switch operator mechanism for a bolted pressure contact switch includes an operating shaft which is latched in the closed condition of the switch contacts against rotation which is urged by the bias of one or more energized springs. Release of the operating shaft latch by a solenoid or a manually actuated mechanism allows the operating shaft to rotate under the bias of the energized springs to an angular position which defines the open condition of the bolted pressure switch contacts.
The operating shaft of the shunt trip operator is also arranged so that it may be rotated manually or by a powered drive mechanism to the closed position of the bolted pressure switch contacts. Closing rotation of the operating shaft usually also energizes both opening and closing springs so that a considerable force must be exerted under these circumstances to rotate the operating shaft. In previous shunt trip operators, the rotation of the operating shaft to close the bolted pressure switch contacts has been accomplished by an electrical motor which was connected by ratchet mechanisms and links to the operating shaft. This previous type of motorized shunt trip operator was expensive to build and somewhat difficult to adjust and maintain. Its installation on a bolted pressure contact switch limited access to one of the fuses.